Fwd: BISECT result: 6.0.0-RC kernels trigger Firefox snap bug with 6.0.0-rc3 through 6.0.0-rc7

Fwd: BISECT result: 6.0.0-RC kernels trigger Firefox snap bug with 6.0.0-rc3 through 6.0.0-rc7

[Mirsad Goran Todorovac]

On 16. 10. 2022. 22:19, Phillip Lougher wrote:
> On 16/10/2022 20:55, Phillip Lougher wrote:
>>
>> Tracking down bugs of this sort is always a process of elimination,
>> and gathering information to pinpoint the exact circumstances of why
>> it is triggering.
>>
>> Next step is to download the exact snap(s) where the problems are 
>> occurring, as this may provide some insights.
>>
>> I don't run Ubuntu, and I don't use snaps.  Can you provide the
>> download link(s) of the snap(s) that cause problems?  If there's
>> any firefox snaps that don't cause problems those will be useful
>> too.
>>
>
> It appears there's a searchable "Snap Store" https://snapcraft.io,
> but, it doesn't give any download links to the actual snaps which
> is rather annoying.
>
> Does anyone know how to get the download link?  I have not run
> Ubuntu for over 14 years and have absolutely no wish to do so
> now either.
>
> Thanks
>
> Phillip
>
>> You don't mention if there's any errors present in "dmesg" when
>> this happens, and so I'm assuming there aren't any?
>>
>> Phillip

Hi, Phillip,

No, there weren't anynew iterms in dmesg -l err output other than these 
usual ones, common to the situations
where the Firefox in snap is working. Only the kernel version is different.

I have managed to reproduce the situation on AlmaLinux 8.6 by installing 
the snapd rpm and then running
a regular "snap install firefox". NOTE: I had to manually enable 
squashfs kernel module.

Otherwise, the Ubuntu 22.04 Firefox 104.x and 105.0.x snaps are also the 
default Firefox snaps from the snap store.

The only exception is that I used 15+ windows and over 200 tabs in the 
testing case, many multimedia Youtube
channels, Yahoo mail, Outlook mail, and quite a few websites. This 
combination triggers the Verdeen errors very
quickly (only on vulnerable 6.0 kernels, on 5.19.x kernels it works like 
a charm).

Thank you.

It is obvious that the snapd + squashfs + Firefox combination triggers 
the bug under heavy load (both on Ubuntu
22.04 jammy and AlmaLinux 8.6.

Hope this helps.

Optionally, I could send the Firefox list of opened windows and tabs if 
I knew where the snaps store it. With the
/usr/bin/firefox version I knew it.

Kind regards,
Mirsad

--
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu
-- 
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia
The European Union

Fwd: BISECT result: 6.0.0-RC kernels trigger Firefox snap bug with 6.0.0-rc3 through 6.0.0-rc7

[Mirsad Goran Todorovac]

On 14. 10. 2022. 23:44, Mirsad Goran Todorovac wrote:
> On 14. 10. 2022. 14:28, Bagas Sanjaya wrote:
>
>> On 10/14/22 17:32, Mirsad Todorovac wrote:
>>> I tried the "make localmodconfig" and provided the default answers 
>>> ([ENTER]) to all questions
>>> the script asked as advised here: 
>>> https://www.stolaf.edu/people/rab/os/linux-compile.html .
>>>
>>> However, though it built much faster, the stripped version did not 
>>> trigger the bug.
>>>
>>> I am now trying to reproduce the bug with v6.0-rc[123] with 
>>> config-{051913,060000}.
>>> This brings a lot of combinations, and though I am a newbie, I 
>>> noticed that build scripts
>>> start with "make clean" for both deb-pkg and rpm-pkg.
>>>
>>> Is there a way to rebuild only the stuff that changed between the 
>>> versions?
>>>
>> You can try building kernel with ccache enabled. However, you'll need
>> to unset build timestamp, since it will make builds non-deterministic:
>>
>>     make CC="ccache gcc" KBUILD_BUILD_TIMESTAMP=""
>>
>> The first ccache build will be slower than normal build, because the
>> object files needs to be written twice (to the output directory and
>> to the cache), though.
>
> Hi, Bagas,
>
> Unfortunately, the ccache command did not work as expected. It still 
> calls the gcc compiler proper,
> even in the second run ...
>
> PID USER      PR  NI    VIRT    RES    SHR S %CPU  %MEM TIME+ COMMAND
> 29213 root      20   0   67420  55100  15676 R  98.1   0.3 0:02.42 
> /opt/alt/python38/bin/python3 /usr/bin/imunify360-agent rstatus
> 29374 mtodorov  30  10  133932 110104  18408 R  98.1   0.7 0:01.46 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./arc+
>  1079 root      20   0  589008 371700   2320 S  97.1   2.3 2343:20 
> /usr/sbin/bacula-fd -f -c /etc/bacula/bacula-fd.conf
> 29425 mtodorov  30  10   95052  71520  16700 R  76.9   0.4 0:00.80 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./arc+
> 29459 mtodorov  30  10   79268  51432  12732 R  46.2   0.3 0:00.48 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./arc+
> 29462 mtodorov  30  10   65516  34828   9224 R  43.3   0.2 0:00.45 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -E -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./+
> 29505 mtodorov  30  10       0      0      0 R  32.7   0.0 0:00.34 [cc1]
> 29506 mtodorov  30  10   65940  38560  12576 R  32.7   0.2 0:00.34 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./arc+
> 29523 mtodorov  30  10   52180  21572   9344 R  17.3   0.1 0:00.18 
> /usr/lib/gcc/x86_64-linux-gnu/8/cc1 -E -quiet -nostdinc -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I ./+
>  5517 root      20   0  780956  77812  10052 S  11.5   0.5 466:39.30 
> /opt/alt/python38/bin/python3 -m im360.run
> 29384 mtodorov  30  10    7132   3964   3568 S  11.5   0.0 0:00.12 
> /usr/local/bin/ccache gcc -Wp,-MMD,sound/i2c/other/.ak4114.o.d 
> -nostdinc -I./arch/x86/include -I./arch/x86/include/generated -I.+
> 29407 mtodorov  30  10    7116   3748   3360 S  10.6   0.0 0:00.11 
> /usr/local/bin/ccache gcc -Wp,-MMD,fs/exfat/.nls.o.d -nostdinc 
> -I./arch/x86/include -I./arch/x86/include/generated -I./include -+
> 29451 mtodorov  30  10    7132   3968   3568 S   9.6   0.0 0:00.10 
> /usr/local/bin/ccache gcc 
> -Wp,-MMD,drivers/pinctrl/intel/.pinctrl-tigerlake.o.d -nostdinc 
> -I./arch/x86/include -I./arch/x86/incl+
> 29522 mtodorov  30  10    8288   7520   1468 R   8.7   0.0 0:00.09 
> scripts/genksyms/genksyms -r /dev/null
> 29524 mtodorov  30  10   17008  12480   3204 R   4.8   0.1 0:00.05 as 
> -I ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I 
> ./arch/x86/include/uapi -I ./arch/x86/include/generated+
>  8896 mtodorov  20   0   12212   4616   3348 R   3.8   0.0 0:04.58 top
>
> 29525 mtodorov  30  10   15028  10412 3248 R   3.8   0.1 0:00.04 as -I 
> ./arch/x86/include -I ./arch/x86/include/generated -I ./include -I 
> ./arch/x86/include/uapi -I ./arch/x86/include/generated+
>
> I used the command line:
> $ make CC="/usr/local/bin/ccache gcc" KBUILD_BUILD_TIMESTAMP="" -j10 
> deb-pkg
>
> I tried to install the latest ccache (version 4.6.3), but it silently 
> calls cc1, despite having 4GiB of cache in $HOME/.ccache ...
>
> I must be doing something wrong. Heavens are not aligned in favour to 
> me this day :-/

Here are the results of the requested bisect on the bug involving the 
Firefox snap build 104.x, 105.0.x, squashfs and which was manifested on 
both Ubuntu snap and with snapd in AlmaLinux 8.6 (CentOS fork):

mtodorov@domac:~/linux/kernel/linux_stable$ git bisect log
git bisect start
# bad: [568035b01cfb107af8d2e4bd2fb9aea22cf5b868] Linux 6.0-rc1
git bisect bad 568035b01cfb107af8d2e4bd2fb9aea22cf5b868
# good: [51dd976781da8c0b47e106ed59a96d7c28972ce4] Linux 5.19.15
git bisect good 51dd976781da8c0b47e106ed59a96d7c28972ce4
# good: [3d7cb6b04c3f3115719235cc6866b10326de34cd] Linux 5.19
git bisect good 3d7cb6b04c3f3115719235cc6866b10326de34cd
# good: [b44f2fd87919b5ae6e1756d4c7ba2cbba22238e1] Merge tag 
'drm-next-2022-08-03' of git://anongit.freedesktop.org/drm/drm
git bisect good b44f2fd87919b5ae6e1756d4c7ba2cbba22238e1
# good: [6614a3c3164a5df2b54abb0b3559f51041cf705b] Merge tag 
'mm-stable-2022-08-03' of 
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
git bisect good 6614a3c3164a5df2b54abb0b3559f51041cf705b
# bad: [eb5699ba31558bdb2cee6ebde3d0a68091e47dce] Merge tag 
'mm-nonmm-stable-2022-08-06-2' of 
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
git bisect bad eb5699ba31558bdb2cee6ebde3d0a68091e47dce
# good: [24df5428ef9d1ca1edd54eca7eb667110f2dfae3] ALSA: hda/realtek: 
Add quirk for HP Spectre x360 15-eb0xxx
git bisect good 24df5428ef9d1ca1edd54eca7eb667110f2dfae3
# good: [c993e07be023acdeec8e84e2e0743c52adb5fc94] Merge tag 
'dma-mapping-5.20-2022-08-06' of 
git://git.infradead.org/users/hch/dma-mapping
git bisect good c993e07be023acdeec8e84e2e0743c52adb5fc94
# good: [4cfa6ff24a9744ba484521c38bea613134fbfcb3] powerpc/64e: Fix 
kexec build error
git bisect good 4cfa6ff24a9744ba484521c38bea613134fbfcb3
# good: [24cb958695724ffb4488ef4f65892c0767bcd2f2] Merge tag 
's390-5.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
git bisect good 24cb958695724ffb4488ef4f65892c0767bcd2f2
# good: [db98b43086275350294f5c6f797249b714d6316d] squashfs: always 
build "file direct" version of page actor
git bisect good db98b43086275350294f5c6f797249b714d6316d
# good: [6ba592fa014f21f35a8ee8da4ca7b95a018f13e8] video: fbdev: s3fb: 
Check the size of screen before memset_io()
git bisect good 6ba592fa014f21f35a8ee8da4ca7b95a018f13e8
# good: [b5a8466d37d30cfcc8015789f4a3f0c44b6c7bc6] Merge tag 
'for-5.20/fbdev-1' of 
git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev
git bisect good b5a8466d37d30cfcc8015789f4a3f0c44b6c7bc6
# bad: [97d3b2676fc6bc4865eb825037f4492f0fb804eb] ocfs2: remove some 
useless functions
git bisect bad 97d3b2676fc6bc4865eb825037f4492f0fb804eb
# bad: [591c32bddbe20ba0e172d9def3c7f22b9c926ad9] kernel/hung_task: fix 
address space of proc_dohung_task_timeout_secs
git bisect bad 591c32bddbe20ba0e172d9def3c7f22b9c926ad9
# bad: [b09a7a036d2035b14636cd4c4c69518d73770f65] squashfs: support 
reading fragments in readahead call
git bisect bad b09a7a036d2035b14636cd4c4c69518d73770f65
mtodorov@domac:~/linux/kernel/linux_stable$

The git bisect stopped at the squashfs commit 
b09a7a036d2035b14636cd4c4c69518d73770f65, so I included Phillip in Cc:, 
according to the Code of Conduct.

Have a nice day!

Kind regards,
Mirsad

(This is a re-send because Thunderbird automatically send MIME unless I 
explicitly set text/plain.)

--
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu
-- 
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia
The European Union